1. Field of the Invention
The present invention relates generally to a cargo restraining clamp for use in refrigeration carriers, such as refrigerated containers or trailers, which does not permanently alter or modify the structure of the refrigerated carrier, and more paritularly the subject invention pertains to a cargo restraining floor clamp for refrigerated carriers having a T-type flooring structure.
Perishable commodities such as meat, vegetables, milk, plants, and also chemicals, are usually transported in refrigerated containers known as reefers, or refrigerated trailers or trucks, all or which are referred to herein as refrigerated carriers. The character of this type of cargo has dictated several criteria in the design of the transport carrier by which it is conveyed. Thus, to assure adequate ventilation to prevent localized spoilage and to improve the overall sanitary environment during transport, the floors of such carriers are usually T shaped or channeled to allow cool air to circulate freely beneath the cargo or the cartons or boxes in which the comestibles are contained. It is also desirable that the interior cargo space of the carriers afford minimum oppurtunity for dirt, grease or debris to accumulate and constitute a possible breeding environment for bacteria. Thus, stakewells or pockets or indentations, which might trap, or act as a repository for, these deleterious materials, are reduced to a minimum or eliminated from the interior surfaces of the carriers as much as possible.
To commence in such refrigerated cargo is often of a one way nature, requiring the use of the refrigerated carrier in one direction only, which results in deadheading (shipping back empty) of the carriers on the return trip, with a consequential loss of valuable cargo space.
Accordingly, the present invention concerns a cargo restraining clamp developed to alleviate the problem of deadheading of special purpose refrigerated carriers by enabling them to be utilizing for the general purpose shipment of cargo.
2. Discussion of the Prior Art
The prior art is replete with designs of special purpose clamping arrangements. For example, Hendricks et al. U.S. Pat. No. 4,311,420 discloses a snubbing block for use in a refrigerated carrier that has an upwardly extending T-handle for expanding an internal wedge clamp against adjacent side walls of a channel floor used in a refrigerated container. Although this reference discloses the use of a removable floor clamp in a refrigerated environment, the physical structure thereof is totally different from that of the subject invention.
Elsner U.S. Pat. No. 2,891,490 discloses a cargo rail tie down for use on a fixed special purpose rail to be mounted in a cargo compartment of an airplane. The clamp has an eyelet tie-down rail, a downwardly extending channel member which grips the tie-down rail, and a horizontal plate that engages cooperating slots formed along the rail. This tie-down, however, does not clamp to the rail, but uses the specially formed slots in the rail to secure it against longitudinal motion.
Laron U.S. Pat. No. 2,867,874 discloses an eye bolt with a clamp and threaded member for clamping the eye bolt to a wooden member.
Howell U.S. Pat. Nos. 4,230,432 and Brunelle 4,449,875 disclose track fasteners or clamps for securing the fastener to a longitudinal rail wherein the fastener has a flange member that is drawn upwardly against the horizontal flanges of the track. These members are clamped against the track by means of a threadable member.
Hain U.S. Pat. No. 2,529,153 discloses a conventional clamp for clamping to a T-member.
However, none of the references discussed hereinabove provides a cargo restraining floor clamp similar to that of the present invention for use with a refrigerated carrier having a T type flooring structure.